Override layer and FBX export issue

Hi,

First many thanks for this awesome plugin!

I have an issue when exporting an humanoid animation to FBX when using override layers. If I don't use any override layer, the hips  orientation (red arrow in the Unity animation preview window) points in the expected direction. As soon as I add an override layer, even without any keyed frame, the red arrow always point forward, and the feet of the character start moving around. The effect is if the hip was still and the feet compensate the movement, loosing al the foot floor placement. The issue doesn't happen if I export to anim file. Many thanks